From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 794FFC43381 for ; Tue, 12 Mar 2019 17:59:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 46F1B214AF for ; Tue, 12 Mar 2019 17:59:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552413563; bh=2ddWb6nN4SwCa4+bDUyaiOY3bgfooQU8Th5bk9InRqg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=OhLhigiupGvDUtYM/aBKfudBMmtvJh4BC2/DJPAa3AMTJKLsMOulVHtMx6Jovvtiu QuOzj1RU/ahdlKmzgYaMdY7wbecPjkRyWoAK4NySghnRBKakADcQz0lpJKfZMIO8eV XQzLL3nkNc43UaVpaTugFs5K3JLisOFPnr9t0824= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728085AbfCLR7W (ORCPT ); Tue, 12 Mar 2019 13:59:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:50740 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727971AbfCLRNd (ORCPT ); Tue, 12 Mar 2019 13:13:33 -0400 Received: from localhost (unknown [104.133.8.98]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E8035217F5; Tue, 12 Mar 2019 17:13:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552410813; bh=2ddWb6nN4SwCa4+bDUyaiOY3bgfooQU8Th5bk9InRqg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X9kQWUqmQsgSuAXz78/p2goTCcXg2Cc87pseT8DXIsIrrxJ/nJ6e9CJbZ1hLh5RFi GTxovtDO00zmeboYk/8aTMNMYtSPfkl8kBR/gxAnsJr+qfbOhbr67mQ1p368EHDQTH uAezAE2s97Zugig2v9Z0ydmywRReGZldl/8X0YcA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mark Syms , Andreas Gruenbacher , Bob Peterson Subject: [PATCH 4.20 165/171] gfs2: Fix missed wakeups in find_insert_glock Date: Tue, 12 Mar 2019 10:09:05 -0700 Message-Id: <20190312170401.640154262@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190312170347.868927101@linuxfoundation.org> References: <20190312170347.868927101@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andreas Gruenbacher commit 605b0487f0bc1ae9963bf52ece0f5c8055186f81 upstream. Mark Syms has reported seeing tasks that are stuck waiting in find_insert_glock. It turns out that struct lm_lockname contains four padding bytes on 64-bit architectures that function glock_waitqueue doesn't skip when hashing the glock name. As a result, we can end up waking up the wrong waitqueue, and the waiting tasks may be stuck forever. Fix that by using ht_parms.key_len instead of sizeof(struct lm_lockname) for the key length. Reported-by: Mark Syms Signed-off-by: Andreas Gruenbacher Signed-off-by: Bob Peterson Signed-off-by: Greg Kroah-Hartman --- fs/gfs2/glock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -107,7 +107,7 @@ static int glock_wake_function(wait_queu static wait_queue_head_t *glock_waitqueue(struct lm_lockname *name) { - u32 hash = jhash2((u32 *)name, sizeof(*name) / 4, 0); + u32 hash = jhash2((u32 *)name, ht_parms.key_len / 4, 0); return glock_wait_table + hash_32(hash, GLOCK_WAIT_TABLE_BITS); }